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Science is amazing.
I know, I know, I say that every other day. But there are times when I read the science news and am completely overwhelmed by how cool it all is, and am frankly astonished by our ability to parse the way the universe works.
The most recent research that provoked that reaction is a paper that appeared in Nature this week entitled, "Natural Speech Reveals the Semantic Maps that Tile Human Cerebral Cortex," by Alexander G. Huth, Wendy A. de Heer, Thomas L. Griffiths, Frédéric E. Theunissen, and Jack L. Gallant. And what this research has done is something I honestly didn't think was possible -- to create a "brain atlas" that maps how words are organized in the cerebrum.
[image courtesy of the Wikimedia Commons]
"Our goal was to build a giant atlas that shows how one specific aspect of language is represented in the brain, in this case semantics, or the meanings of words," said study author Gallant, a neuroscientist at the University of California, Berkeley. As science writer Ian Sample of The Guardian put it:
The atlas shows how words and related terms exercise the same regions of the brain. For example, on the left-hand side of the brain, above the ear, is one of the tiny regions that represents the word "victim." The same region responds to "killed," "convicted"," "murdered" and "confessed." On the brain’s right-hand side, near the top of the head, is one of the brain spots activated by family terms: "wife," "husband," "children," "parents."Further, as many words have more than one definition, the researchers were able to map how context influences meaning and changes the site of brain activation. The word "top," for example, can mean a child's toy, a woman's shirt, or can be a relational word that describes position.
The study's authors write:
We show that the semantic system is organized into intricate patterns that seem to be consistent across individuals. We then use a novel generative model to create a detailed semantic atlas. Our results suggest that most areas within the semantic system represent information about specific semantic domains, or groups of related concepts, and our atlas shows which domains are represented in each area. This study demonstrates that data-driven methods—commonplace in studies of human neuroanatomy and functional connectivity—provide a powerful and efficient means for mapping functional representations in the brain.The research is groundbreaking. Lorraine Tyler, cognitive neuroscientist and head of the Centre for Speech, Language and the Brain at Cambridge University, described it as "a tour de force" -- a phrase scientists don't use lightly. There is already talk of using the research to allow people who are unable to speak for reasons of illness or injury, but whose other cognitive processes are undamaged, to communicate with speech-production software via a brain/computer interface. What other applications might come up are mind-bending even to consider. Uri Hasson, a neuroscientist at Princeton, said, "There are so many implications... we are barely touching the surface."
So once again, it's science for the win. It's heartening to think, in this age where I'm often afraid to open up the newspaper for fear of finding out what new and unusual ways we've come up with to be horrible to one another, that we are capable of elegant and beautiful research that elucidates how our own minds work. As Carl Sagan put it, "We are a way for the cosmos to know itself."
The paper's authors write:
We show that the semantic system is
organized into intricate patterns that seem to be consistent across individuals. We then use a novel generative model to
create a detailed semantic atlas. Our results suggest that most areas within the semantic system represent information
about specific semantic domains, or groups of related concepts, and our atlas shows which domains are represented in
each area. This study demonstrates that data-driven methods—commonplace in studies of human neuroanatomy and
functional connectivity—provide a powerful and efficient means for mapping functional representations in the brain.
We show that the semantic system is
organized into intricate patterns that seem to be consistent across individuals. We then use a novel generative model to
create a detailed semantic atlas. Our results suggest that most areas within the semantic system represent information
about specific semantic domains, or groups of related concepts, and our atlas shows which domains are represented in
each area. This study demonstrates that data-driven methods—commonplace in studies of human neuroanatomy and
functional connectivity—provide a powerful and efficient means for mapping functional representations in the brain.
We show that the semantic system is
organized into intricate patterns that seem to be consistent across individuals. We then use a novel generative model to
create a detailed semantic atlas. Our results suggest that most areas within the semantic system represent information
about specific semantic domains, or groups of related concepts, and our atlas shows which domains are represented in
each area. This study demonstrates that data-driven methods—commonplace in studies of human neuroanatomy and
functional connectivity—provide a powerful and efficient means for mapping functional representations in the brain.
